ALT XING RESTR. THE FLC ENTER DATA INCORRECTLY IN THE FMC AND CROSS THE RESTR TOO HIGH.

Narrative

THE CAPT WAS THE PF ON OUR B-767 FLYING N ON J-53 FROM CHARLOTTE TO PITTSBURGH AT FL290. THE ACFT WAS ON THE AUTOPLT. ATC ISSUED US A XING RESTR TO CROSS 30 MI S OF RICCS INTXN AT FL240. IF RICCS WAS OUR NEXT INTXN; WE COULD HAVE EASILY BUILT OUR XING RESTR WAYPOINT AS AN 'ALONG TRACK WAYPOINT' BY ENTERING RICCS/-30 AND INSERTING IT BEFORE RICCS. HOWEVER; SINCE THERE WERE SEVERAL WAYPOINTS BTWN OUR POS AND RICCS; THIS SIMPLE METHOD WOULD NOT WORK. INSTEAD; THE CAPT LOOKED AT OUR LEGS PAGE; AND TRIED TO ADD SEVERAL WAYPOINTS BACK FROM RICCS TO SEE IF HE COULD FIND A WAYPOINT WHICH WAS 30 MI S OF RICCS. BEING UNSUCCESSFUL; HE ASKED ME TO JUST PUT THE XING RESTR AT PERRI INTXN. I BACKED UP THE CAPT'S ARITHMETIC COMPUTATIONS; AND AGREED TO ENTER THE RESTR AT PERRI INTXN; WHICH I CALCULATED WAS ACTUALLY 39 MI S OF RICCS (THE NEXT INTXN N OF PERRI WOULD HAVE BEEN TOO SHORT; BEING ONLY 16 MI S OF RICCS). I ENTERED FL240 AND ENTERED IT IN THE POS NEXT TO PERRI; OR SO I THOUGHT. AS I WAS DOING THIS I GLANCED AT THE CAPT TO BE SURE HE WAS MONITORING MY ENTRY AND I VERBALLY SAID SOMETHING SIMILAR TO 'FL240 AT PERRI.' I SAW THAT THE CAPT WAS INDEED MONITORING MY ENTRY AND NODDED AN APPROVAL. THE CAPT AND I VERIFIED THAT 24000 FT WAS SET IN OUR ALT WINDOW; AND I CHKED TO MAKE SURE WE WERE STILL IN VNAV; AND NOTICED A TOP OF DSCNT POINT NOT TOO FAR AHEAD OF US ON OUR MAP. I FELT CONFIDENT THE ACFT WOULD CROSS 39 MI S OF RICCS AT FL240. RIGHT AFTER THIS WE HAD 2 COMPANY PLTS SITTING ON OUR COCKPIT JUMPSEATS INITIATE SOME DETAILS OF OUR NEW PROPOSED PLT PAYCUTS AND CONCESSIONS TO OUR COMPANY MGMNT. THIS WAS NEW AND DISTURBING INFO TO ME; AND I FELT BOTH THE CAPT AND I WERE SOMEWHAT DISTRACTED FROM MONITORING THE DSCNT OF THE ACFT BY THESE PLTS REVEALING THIS INFO. ATC THEN CALLED US AND WANTED TO KNOW WHEN WE WERE GOING TO START OUR DSCNT. I LOOKED AT THE CRUISE PAGE AND SAW AND RPTED WE WOULD START DOWN IN 4 MI. ATC ACKNOWLEDGED MY CALL AND SEEMED SATISFIED; AND THIS MADE ME FEELTHAT THERE WAS NO PROB WITH OUR DSCNT PLANNING. THE ACFT STARTED DSNDING AT WHICH WE THOUGHT WAS THE PROPER TOP OF DSCNT POINT. THEN ATC CALLED BACK AND ASKED IF WE UNDERSTOOD OUR XING RESTR. AT THIS TIME I LOOKED AGAIN AT THE DSCNT PAGE AND AT OUR DSCNT GS ON THE R SIDE OF OUR MAP AND BOTH SHOWED US RIGHT ON OUR DSCNT PROFILE. THEN MY THOUGHTS TURNED TO OUR DEP FROM CHARLOTTE. IMMEDIATELY AFTER LEAVING CHARLOTTE; ATC QUESTIONED US ON OUR ALT; AND THEY DETERMINED THAT OUR MODE C ALT RPTING WAS ABOUT 1000 FT OFF. WE SWITCHED TO OUR OTHER XPONDER AND ATC RESPONDED THAT OUR RPTED ALT WAS NOW THE SAME AS WHAT WAS SHOWING ON THEIR SCREEN. I THOUGHT THAT WE WERE POSSIBLY HAVING MORE MODE C ALT RPTING PROBS; AND IT STILL DID NOT OCCUR TO ME THAT WE WERE HAVING A XING RESTR PROB. I LOST SOME PRECIOUS TIME HERE THAT COULD HAVE BEEN USED TO ALERT ATC OF OUR ERROR A LITTLE SOONER. I LOOKED AT OUR MAP AND SAW THAT RICCS INTXN SEEMED CLOSER TO OUR POS THAN IT SHOULD HAVE BEEN. AT THIS TIME I FELT THAT THERE WAS SOMETHING WRONG WITH OUR XING RESTR. I IMMEDIATELY SCANNED OUTSIDE AGAIN TO LOOK FOR POSSIBLE CONFLICTING TFC SINCE THE WX WAS GOOD VFR (I SAW NO ACFT). I QUICKLY LOOKED AT OUR TCASII TO SEE IF THERE WAS ANY TFC SHOWING IN OUR AREA (THERE WAS NO TFC SHOWN NEARBY); AND I CALLED ATC TO RPT OUR DSNDING ALT SO THEY WOULD BE AWARE OF OUR SIT AND COULD ISSUE VECTORS OR INSTRUCTIONS TO US OR POSSIBLE CONFLICTING TFC. ATC SEEMED TO BE AWARE OF OUR MISSED XING RESTR; BUT DID NOT SAY ANYTHING ABOUT ANY CONFLICTING TFC IN THE AREA; AND ISSUED A FREQ CHANGE FOR US WITHOUT ANY FURTHER DISCUSSION. I QUICKLY CHKED IN ON THE NEW FREQ AND RPTED LEVEL AT FL240; SINCE WE HAD LEVELED OFF BY THIS TIME. THE NEW CTLR DID NOT ASK ANYTHING ABOUT OUR PREVIOUS XING RESTR AND SEEMED SATISFIED WITH OUR ALT AND POS. I BELIEVE MY ENTRY OF FL240 ENDED UP NEXT TO PERKS INTXN INSTEAD OF MY INTENDED ENTRY NEXT TO PERRI INTXN. I THINK THAT JUST BEFORE I PUT FL240 NEXT TO PERRI; WE PASSED A WAYPOINT ON OUR RTE AND THEN THE WAYPOINTS ON OUR LEGS PAGE ALL SCROLLED UP ONE WAYPOINT SO THAT JUST 1/2 A SECOND BEFORE MY ENTRY THE WAYPOINT CHANGED FROM PERRI TO PERKS; AND BOTH THE CAPT AND I DID NOT CATCH THIS. IF THESE INTXNS WERE NOT SO SIMILAR IN NAME (BOTH START WITH PER) WE MAY HAVE CAUGHT OUR ERROR. AS A PLT; I WILL BE ON THE LOOKOUT FOR THIS POTENTIAL SIT TO HAPPEN AGAIN; AND WILL DOUBLE-CHK TO SEE IF THE XING ALT DID IN FACT END UP NEXT TO THE PROPER WAYPOINT. I WILL ALSO PUT THE WAYPOINT ON THE FIX PAGE AND MONITOR IT AS A BACKUP TO VERIFY THAT WE ARE ON A PROPER DSCNT PROFILE. I WOULD RECOMMEND TO ATC TO GIVE XING RESTRS TO ACFT EQUIPPED WITH A FMS AT A SPECIFIC WAYPOINT ALONG THE RTE. THIS WOULD MINIMIZE THE POTENTIAL FOR AN ERROR. ALSO I FEEL CHANGING SIMILAR APPEARING NAMES SUCH AS PERRI AND PERKS COULD MINIMIZE THE POTENTIAL FOR ERROR.